I use Windows 7 Home Premium. On the first screen-shot you see two instances of Adobe CEF running and that's causing MCP to wait. When I kill the first process, MPC immediately starts playing video and that's what you see on the second screen-shot.

I'm sorry, I had lots of work to do. Well, I did that and it worked. So I supposed that was some problems with codecs. I reinstalled my codecs (K Lite 11) and it worked. Now everything is fine. Case could be closed.